1. Technical Field
The present invention relates to projectors.
2. Related Art
In the past, the configuration of a projector in which, in an exhaust port formed in an outer housing, a plurality of louver boards (louvers) for opening and closing the exhaust port are provided has been proposed (for example, JP-A-2003-315910 (Patent Document 1)).
In a projector (a projecting device) of Patent Document 1, a structure (hereinafter an “opening and closing structure”) in which a plurality of louver boards are rotatably attached to an outer housing (an outer part) and an exhaust port can be opened and closed by rotating the louver boards is adopted.
Specifically, the opening and closing structure includes an arm which has the shape of an long flat plate and moves rectilinearly in a longitudinal direction. Moreover, each of the plurality of louver boards is provided with a louver guide shaft which is parallel to a louver rotation axis. The louver guide shafts are inserted in long holes (arm guiding holes) formed in the arm.
A force is exerted on each louver guide shaft at an inner edge of each long hole by moving the arm rectilinearly in a longitudinal direction, whereby the louver boards are rotated at once.
However, in the projector of Patent Document 1, the positions of the louver guide shaft in a close position in which the exhaust port is closed by the louver boards and in an open position in which the exhaust port is opened by the louver boards are not set so as to be located on opposite sides of a virtual plane which includes the rotation axis of the louver board and is perpendicular to a direction in which the arm moves (a longitudinal direction).
That is, when the louver board is rotated from the open position to the close position or rotated from the close position to the open position, the louver guide shaft moves in an arc so as to intersect with the direction in which the arm moves.
As a result, a somewhat great force is required to move the arm (rotate the louver boards) and a great driving force is required to open and close the exhaust port smoothly by rotating the louver boards, which is a first problem.
Moreover, in the projector of Patent Document 1, even when the exhaust port is closed by rotating the louver boards, the louver boards sway due to a gap etc. between each long hole formed in the arm and the louver guide shaft, making it difficult to keep a state in which the exhaust port is closed, which is a second problem.